A.V. Barkhatov

The altitude profile (AP) of the electron density (ED) in the ionosphere is used when ones determine the target coordinates with HF radar. To determine the AP it is necessary some model of the ED distribution in the ionosphere. The main parameters of the model (F2 maximum electron density, the height of the F2 maximum electron density, etc.) are refined with data of vertical or oblique sounding system, but refinement does not allow to eliminate completely errors in the AP. The errors in the AP result in errors of the target coordinate determination. The statistical experiment can be used to estimate the target coordinate measurement errors depending on AP determination errors. The statistical simulated experiment carried out for various the one-step low latitude ionosphere propagation paths shows that the relative standard deviation of estimation of the main parameters of IRI model equal to 5 % results in average location error of about 6 km at a distance of 1000 km. With the increase of distance the average location error derived from the AP determination errors is reduced to about 3 km. Relative standard deviation of estimation of the main parameters of IRI model equal to 10 % results in target location error from 10 to 20 km for different propagation paths at a distance of 1000 km. With the increase of distance it reduces to about 4 km. There is variation of estimation of the target location error for different the propagation paths with the same distance of target. It is due to the change of length of propagation paths in different ionosphere conditions.